JP2015037175A - Multilayer ceramic electronic component, and method for manufacturing the same and mounting board for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer ceramic electronic component, and a method for manufacturing the same and a mounting board for the same.SOLUTION: A multilayer ceramic electronic component 100 comprises: a ceramic body 110 which includes a plurality of dielectric layers 111 laminated in a thickness direction and satisfies T/W>1.0, where W is the width thereof and T is the thickness thereof; a plurality of first and second internal electrodes 121, 122 which are arranged to face each other through the dielectric layers 111 in the ceramic body 110 and exposed alternately through both end surfaces of the ceramic body 110; and first and a second external electrodes 131, 132 which includes head parts 131a, 132a formed on both end surfaces of the ceramic body and two band parts 131b, 132b connected to head parts and formed on upper and lower main surfaces of the ceramic body while being separated from each other in the width direction, and are electrically connected to first and second internal electrodes.

Description

  The present invention relates to a multilayer ceramic electronic component, a manufacturing method thereof, and a mounting substrate thereof.

  Recently, due to the trend toward miniaturization of electronic products, there has been a demand for miniaturization and high capacity of multilayer ceramic electronic components used in the electronic products.

  As a result, thinning and multilayering of dielectric layers and internal electrodes have been attempted by various methods, and recently, multilayer ceramic electronic parts having a thin dielectric layer and an increased number of laminated layers have been manufactured.

  While the multilayer ceramic electronic component can be miniaturized and the dielectric layer and the internal electrode can be made thin, the number of layers can be increased in order to realize high capacity.

  However, if the number of stacks is increased while the dielectric layers and internal electrodes are thinned as described above, the high capacity of the multilayer ceramic electronic component can be realized. It becomes a big form.

  As described above, when the thickness of the multilayer ceramic electronic component is formed to be larger than the width, generally, the external electrodes formed on both end faces of the multilayer ceramic electronic component have a round shape with protruding peripheral surfaces.

  Therefore, when mounting a multilayer ceramic electronic component on a printed circuit board or the like, there is a frequent problem that the multilayer ceramic electronic component cannot be maintained in a state where it is mounted, and the mounting failure rate of the multilayer ceramic electronic component increases. There is a point.

  Patent Document 1 below discloses a multilayer ceramic capacitor corresponding to downsizing and high capacity, but does not disclose means for solving the problem of falling when the multilayer ceramic capacitor is mounted on a printed circuit board. .

JP 2005-129802 A

  In this technical field, as the number of stacks increases, the thickness becomes larger than the width, and while realizing high capacity, it solves the problem of falling down when mounting multilayer ceramic electronic components on printed circuit boards, etc. There has been a demand for new ways to reduce the occurrence of defects and shorts.

  One aspect of the present invention includes a ceramic body that includes a plurality of dielectric layers stacked in the thickness direction, satisfying T / W> 1.0 when the width is defined as W and the thickness is defined as T, and the ceramic A plurality of first and second internal electrodes disposed opposite to each other through the dielectric layer in the body and exposed alternately through both end faces of the ceramic body; and heads formed on both end faces of the ceramic body; and The upper and lower main surfaces of the ceramic body are connected to the head, and include two band portions formed to be spaced apart from each other in the width direction, and are electrically connected to the first and second internal electrodes, respectively. Provided is a multilayer ceramic electronic component including first and second external electrodes.

  Another aspect of the present invention includes a ceramic body that includes a plurality of dielectric layers stacked in the width direction and satisfies T / W> 1.0 when the width is defined as W and the thickness is defined as T, and the ceramic A plurality of first and second internal electrodes disposed opposite to each other through the dielectric layer in the body and exposed alternately through both end faces of the ceramic body; and heads formed on both end faces of the ceramic body; and The upper and lower main surfaces of the ceramic body are connected to the head, and include two band portions formed to be spaced apart from each other in the width direction, and are electrically connected to the first and second internal electrodes, respectively. Provided is a multilayer ceramic electronic component including first and second external electrodes.

  According to still another aspect of the present invention, a plurality of ceramic sheets on which the first and second internal electrodes are formed are stacked and pressed so that the first and second internal electrodes are arranged to face each other through the ceramic sheet. Providing a multilayer body, cutting the multilayer body into regions corresponding to one capacitor, firing, and opposing the first and second main surfaces in the thickness direction, the first and second internal electrodes. Providing a ceramic body having first and second end faces in the lengthwise direction, and first and second side faces in the widthwise direction that are alternately exposed, and electrically connecting the first and second internal electrodes to the ceramic body. Forming the first and second external electrodes to be connected to each other, and forming the first and second external electrodes in the thickness-width cross section of the ceramic body. And the second main surface and the first and second sides. A laminate in which a conductive paste is applied to both corners in contact with each other to form heads on the first and second end faces and to form two band parts so as to be separated from each other on the first and second main faces A method for manufacturing a ceramic electronic component is provided.

  In one embodiment of the present invention, in the step of providing the laminate, the ceramic sheets may be laminated in the thickness direction or in the width direction.

  In one embodiment of the present invention, when the width of the ceramic body is defined as W and the width of the band portion is defined as a, 0.10 ≦ a / W ≦ 0.45 can be satisfied.

  In one embodiment of the present invention, when the thickness of the band portion is defined as S, 2 ≦ S ≦ 40 μm can be satisfied.

  According to an embodiment of the present invention, the multilayer ceramic electronic component is printed by forming the external electrode to include two band portions that are spaced apart from each other, while increasing the number of layers to realize a high capacity. This prevents the phenomenon of falling when mounted on a circuit board or the like, and reduces the mounting defect rate and occurrence of short circuits.

1 is a perspective view schematically showing a multilayer ceramic capacitor in accordance with an embodiment of the present invention by cutting a part thereof. It is sectional drawing of the AA 'line of FIG. FIG. 5 is a perspective view schematically showing a multilayer ceramic capacitor in accordance with another embodiment of the present invention cut away. It is sectional drawing of the BB 'line | wire of FIG. 1 is a perspective view schematically showing a state in which a multilayer ceramic capacitor according to an embodiment of the present invention is mounted on a printed circuit board by cutting a part of the multilayer ceramic capacitor.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention can be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. In addition, the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. The shape and size of elements in the drawings may be exaggerated for a clearer description.

  Hereinafter, a multilayer ceramic electronic component according to an embodiment of the present invention will be described using a multilayer ceramic capacitor, but the present invention is not limited to this.

Multilayer Ceramic Capacitor FIG. 1 is a perspective view schematically showing a part of a multilayer ceramic capacitor according to an embodiment of the present invention.

  Referring to FIG. 1, a multilayer ceramic capacitor 100 according to an embodiment of the present invention includes a ceramic body 110, a plurality of first and second internal electrodes 121 and 122, first and second external electrodes 131 and 132, including.

  The ceramic body 110 is formed by laminating a plurality of dielectric layers 111 in the thickness direction and then firing, and a boundary between adjacent dielectric layers 111 is not used by using a scanning electron microscope (SEM: Scanning Electron Microscope). May be integrated so as not to be confirmed.

  The shape of the ceramic body 110 is not particularly limited, and may be a hexahedral shape, for example.

  In order to clearly describe the embodiment of the present invention, the hexahedral direction of the ceramic body 110 is defined. L, W, and T shown in the drawing are a length direction, a width direction, and a thickness direction, respectively.

  Further, in the present embodiment, for convenience of explanation, the opposing surfaces in the thickness direction of the ceramic body 110 are connected to the first and second main surfaces, and the first and second main surfaces are connected in the opposing length direction. Surfaces are defined as first and second end surfaces, and opposing width-direction surfaces are defined as first and second side surfaces.

  The ceramic body 110 has a configuration in which the number of stacked dielectric layers 111 is increased in order to realize a high capacity. When the width is defined as W and the thickness is defined as T, T / W> 1.0 is satisfied. The thickness is larger than the width of the ceramic body 110.

The dielectric layer 111 can include a ceramic material having a high dielectric constant. For example, the dielectric layer 111 may include a barium titanate (BaTiO ₃ ) -based ceramic powder or the like as long as a sufficient capacitance can be obtained.

  In addition to the ceramic powder, the dielectric layer 111 may include various types of ceramic additives such as transition metal oxides or carbides, rare earth elements, magnesium (Mg), aluminum (Al), and the like, if necessary. Organic solvents, plasticizers, binders, dispersants and the like may be further added.

  The first and second internal electrodes 121 and 122 are electrodes having different polarities, and are arranged to face each other through a ceramic sheet forming the dielectric layer 111, and the first and second of the ceramic body 110 are within the ceramic body 110. You may form so that it may each expose through an end surface.

  At this time, the first and second internal electrodes 121 and 122 may be electrically insulated from each other by the dielectric layer 111 disposed in the middle.

  In addition, the first and second internal electrodes 121 and 122 are formed of a conductive metal, for example, one of silver (Ag), palladium (Pd), platinum (Pt), nickel (Ni), and copper (Cu). Alternatively, an alloy made of these alloys may be used, but the present invention is not limited to this.

  The first and second external electrodes 131 and 132 are respectively formed with first and second heads 131a and 132a formed on the first and second end surfaces of the ceramic body 110, and first and second heads 131a and 132a, respectively. And two first and second band portions 131b and 132b that are connected to each other and are spaced apart from each other in the width direction on the first and second main surfaces of the ceramic body 110.

  The first and second heads 131a and 132a are electrically connected to the plurality of first and second internal electrodes 121 and 122 that are alternately exposed through the first and second end faces. The first and second band portions 131b and 132b become mounting portions when mounted on a printed circuit board or the like.

  At this time, the first and second external electrodes 131 and 132 are provided on the first and second side surfaces of the ceramic body 110 to improve moisture resistance, and the first and second heads 131a and 132a and the first and second bands. The first and second side surface connection parts 131c and 132c may be included so as to be connected to the parts 131b and 132b.

  The first and second external electrodes 131 and 132 are made of a conductive metal, and may be made of, for example, silver (Ag), nickel (Ni), copper (Cu), or the like. The first and second external electrodes 131 and 132 may be formed by applying a conductive paste prepared by adding glass frit to the conductive metal powder, followed by baking. It is not limited to.

  Meanwhile, first and second plating layers (not shown) may be formed on the first and second band portions 131b and 132b as necessary.

  The first and second plating layers are for increasing the adhesive strength between the multilayer ceramic capacitor 100 when it is mounted on the printed circuit board by soldering.

  The first and second plating layers include, for example, a nickel (Ni) plating layer formed on the first and second band portions 131b and 132b, and a tin (Sn) plating layer formed on the nickel plating layer. The present invention is not limited to this.

  FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1 and shows a thickness-width cross section of the multilayer ceramic capacitor according to the embodiment of the present invention.

  Referring to FIG. 2, when the width of the ceramic body 110 is defined as W and the width of the band portions 131b and 132b of the external electrode is defined as a, 0.10 ≦ a / W ≦ 0.45 can be satisfied.

  Table 1 above shows the results of experiments on the presence or absence of chip collapse and the presence or absence of reliability failure during mounting based on the a / W value.

  Referring to Table 1 above, sample 1 with an a / W of 0.05 collapses 3 out of 50 chips when mounted, and in an experiment with poor reliability, 2 out of 200 chips found defects It was done.

  Further, in the sample 10 in which a / W is 0.50, four of the 50 chips collapsed during mounting, and in the reliability failure experiment, one of the 200 chips was found defective.

  On the other hand, in Samples 2 to 9 in which a / W is within the scope of the present invention, chip collapse and poor reliability were not found during mounting.

  Further, when the thickness of the band portions 131b and 132b is defined as S, the range of 2 ≦ S ≦ 40 μm can be satisfied.

  Table 2 above shows the results of experiments on whether or not the chip collapses during mounting based on the S value and whether or not the reference capacity is satisfied.

  Referring to Table 2 above, it can be seen that Sample 1 with S of 1 μm collapses five of the 50 chips when mounted, and Samples 8 and 9 with S over 40 μm do not satisfy the reference capacity. In particular, not only the sample 9 did not satisfy the reference capacity, but also 3 of the 50 collapsed during mounting.

Modification FIG. 3 is a perspective view schematically showing a multilayer ceramic capacitor in accordance with another embodiment of the present invention.

  Here, since the structure in which the first and second external electrodes 131 and 132 are formed is the same as that in the above-described embodiment, a specific description thereof is omitted to avoid duplication and is different from the above-described embodiment. The first and second internal electrodes 121 ′ and 122 ′ having a structure will be specifically described.

  Referring to FIG. 3, a multilayer ceramic capacitor 100 ′ according to another embodiment of the present invention includes a ceramic body 110 in which a plurality of dielectric layers 111 are stacked in the width direction.

  Accordingly, the first and second internal electrodes 121 ′ and 122 ′ are arranged in the width direction so as to face each other with the ceramic sheet forming the dielectric layer 111 therebetween. It may be formed so as to be exposed through the second end face. At this time, the first and second internal electrodes 121 ′ and 122 ′ may be electrically insulated from each other by the dielectric layer 111 disposed in the middle.

  FIG. 4 is a cross-sectional view taken along the line BB ′ of FIG. 3 and shows a thickness-width cross section of a multilayer ceramic capacitor according to another embodiment of the present invention.

  Referring to FIG. 4, when the width of the ceramic body 110 is defined as W and the width of the band portions 131b and 132b of the external electrode is defined as a, 0.10 ≦ a / W ≦ 0.45 can be satisfied.

  Further, when the thickness of the band portions 131b and 132b is defined as S, the range of 2 ≦ S ≦ 40 μm can be satisfied.

Method for Manufacturing Multilayer Ceramic Capacitor Hereinafter, a method for manufacturing a multilayer ceramic capacitor according to an embodiment of the present invention will be described.

  First, a plurality of ceramic sheets are prepared. The ceramic sheet is used to form the dielectric layer 111 of the ceramic body 110. A ceramic powder, a polymer and a solvent are mixed to produce a slurry, and the slurry is applied onto a carrier film by a method such as a doctor blade. And it dries and manufactures in the sheet form of thickness of several micrometers.

  Next, the first and second internal electrodes 121 and 122 are formed on at least one surface of the ceramic sheet by printing a conductive paste at a predetermined interval and a predetermined thickness in the length direction.

  As a printing method of the conductive paste for forming the internal electrode pattern, a screen printing method or a gravure printing method may be used, and the present invention is not limited to this.

  Next, a plurality of ceramic sheets on which the internal electrode patterns are formed are stacked and pressed from the stacking direction to provide a stack. At this time, the stacked body may be configured such that the internal electrode patterns are stacked in the thickness direction or stacked in the width direction with reference to the mounting surface.

  Next, the laminate is cut into regions corresponding to one capacitor in accordance with 0603 (length × width) standard, and the thickness / width exceeds 1.0, and the first in the opposing thickness direction is cut. Then, a chip having first and second end surfaces in the length direction and first and second side surfaces in the width direction in which the first and second inner electrodes 121 and 122 are alternately exposed is formed. Then, after firing at a high temperature of 1050 to 1200 ° C., the ceramic body 110 is provided by polishing.

  Next, the first and second external electrodes 131 and 132 are electrically connected to the exposed portions of the first and second internal electrodes 121 and 122 on the first and second end surfaces of the ceramic body 110, respectively. Form.

  At this time, the first and second external electrodes 131 and 132 are electrically conductive paste at both corners where the first and second main surfaces and the first and second side surfaces are in contact with each other in the thickness-width section of the ceramic body 110. To form head portions 131a and 132a on the first and second end surfaces, and to form two band portions 131b and 132b so as to be spaced apart from each other on the first and second main surfaces.

  In addition, if necessary, after the step of forming the first and second external electrodes 131 and 132, the surfaces of the first and second band portions 131b and 132b are plated by a method such as electroplating to form the first and first external electrodes 131 and 132. Two plating layers (not shown) can be formed.

  At this time, when the width of the ceramic body 110 is defined as W and the width of the band portions 131b and 132b of the external electrode is defined as a, 0.10 ≦ a / W ≦ 0.45 can be satisfied.

FIG. 5 is a perspective view schematically showing a state in which a multilayer ceramic capacitor according to an embodiment of the present invention is mounted on a printed circuit board by partially cutting the multilayer ceramic capacitor.

  Referring to FIG. 5, the mounting substrate 200 of the multilayer ceramic capacitor 100 according to the present embodiment is formed on the upper surface of the printed circuit board 210 and the printed circuit board 210 on which the multilayer ceramic capacitor 100 is mounted horizontally or vertically. First and second electrode pads 221 and 222.

  At this time, the multilayer ceramic capacitor 100 is positioned such that the first and second band portions 131b and 132b of the first and second external electrodes 131 and 132 are in contact with the first and second electrode pads 221 and 222, respectively. In this state, the printed circuit board 210 may be electrically connected by soldering 230.

  Although the embodiment of the present invention has been described in detail above, the scope of the right of the present invention is not limited to this, and various modifications and modifications can be made without departing from the technical idea of the present invention described in the claims. It will be apparent to those skilled in the art that variations are possible.

100, 100 'Multilayer ceramic capacitor 110 Ceramic body 111 Dielectric layers 121, 121', 122, 122 'First and second internal electrodes 131, 132 First and second external electrodes 131a, 132a First and second heads 131b, 132b first and second band portions 131c, 132c first and second side surface connecting portions

Claims (14)

A ceramic body that includes a plurality of dielectric layers stacked in the thickness direction and satisfies T / W> 1.0 when the width is defined as W and the thickness is defined as T;
A plurality of first and second internal electrodes disposed opposite to each other through the dielectric layer in the ceramic body, and alternately exposed at both end faces of the ceramic body;
A head portion formed on both end surfaces of the ceramic body; and two band portions connected to the head portion and formed on the upper and lower main surfaces of the ceramic body so as to be spaced apart from each other in the width direction. And first and second external electrodes electrically connected to the second internal electrode, respectively.
Including multilayer ceramic electronic components.   2. The multilayer ceramic electronic component according to claim 1, wherein 0.10 ≦ a / W ≦ 0.45 is satisfied when the width of the ceramic body is defined as W and the width of the band portion is defined as a.   The multilayer ceramic electronic component according to claim 1, wherein when the thickness of the band portion is defined as S, 2 ≦ S ≦ 40 μm is satisfied. A ceramic body that includes a plurality of dielectric layers stacked in the width direction and satisfies T / W> 1.0 when the width is defined as W and the thickness is defined as T;
A plurality of first and second internal electrodes disposed opposite to each other through the dielectric layer in the ceramic body, and alternately exposed at both end faces of the ceramic body;
A head portion formed on both end surfaces of the ceramic body, and two band portions connected to the head portion and formed on the upper and lower main surfaces of the ceramic body so as to be spaced apart from each other in the width direction; First and second external electrodes electrically connected to the first and second internal electrodes, respectively;
Including multilayer ceramic electronic components.   5. The multilayer ceramic electronic component according to claim 4, wherein 0.10 ≦ a / W ≦ 0.45 is satisfied when the width of the ceramic body is defined as W and the width of the band portion is defined as a.   The multilayer ceramic electronic component according to claim 4, wherein when the thickness of the band portion is defined as S, 2 ≦ S ≦ 40 μm is satisfied. A printed circuit board having first and second electrode pads on top;
A multilayer ceramic electronic component mounting board comprising: the multilayer ceramic electronic component according to any one of claims 1 to 6 provided on the first and second electrode pads. Laminating a plurality of ceramic sheets on which the first and second internal electrodes are formed so that the first and second internal electrodes are opposed to each other through the ceramic sheet, and pressing to form a laminate;
The multilayer body is cut and fired for each region corresponding to one capacitor, and the first and second main surfaces in the thickness direction facing each other and the lengths at which the first and second internal electrodes are alternately exposed. Forming a ceramic body having first and second end faces in the direction and first and second side faces in the width direction;
Forming first and second external electrodes on the ceramic body so as to be electrically connected to the first and second internal electrodes;
In the step of forming the first and second external electrodes, in the thickness-width section of the ceramic body, a conductive paste is applied to both end portions where the first and second main surfaces are in contact with the first and second side surfaces. Manufacturing a multilayer ceramic electronic component in which a head is formed on each of the first and second end surfaces by coating and two band portions are formed on the first and second main surfaces so as to be spaced apart from each other in the width direction. Method.   The method of manufacturing a multilayer ceramic electronic component according to claim 8, wherein the step of providing the multilayer body includes laminating the ceramic sheets in a thickness direction.   10. The multilayer ceramic electronic component of claim 9, wherein when the width of the ceramic body is defined as W and the width of the band portion is defined as a, 0.10 ≦ a / W ≦ 0.45 is satisfied. Production method.   11. The method for manufacturing a multilayer ceramic electronic component according to claim 9, wherein when the thickness of the band portion is defined as S, 2 ≦ S ≦ 40 μm is satisfied.   The method of manufacturing a multilayer ceramic electronic component according to claim 8, wherein the step of providing the multilayer body includes laminating the ceramic sheets in a width direction.   13. The multilayer ceramic electronic component of claim 12, wherein 0.10 ≦ a / W ≦ 0.45 is satisfied when the width of the ceramic body is defined as W and the width of the band portion is defined as a. Production method.   14. The method of manufacturing a multilayer ceramic electronic component according to claim 12, wherein when the thickness of the band portion is defined as S, 2 ≦ S ≦ 40 μm is satisfied.

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